On the second day of this year's South by Southwest Music Conference and Festival, Philadelphia-based Free Energy, like other buzzed-about acts, played the Levi's Fader Fort, a weeklong party that has become one of the most popular events for music fans who don't bother with a wristband. The group, whose music has drawn comparisons to a host of classic rock bands from the 1970s, released their debut album digitally in the beginning of March. They came to Austin equipped with marketing materials meant to help get their music heard, and they handed out what some might consider a curious artifact - cassette tapes.

"The only people who listen to CDs now are old people and people who sold their vinyl collection and bought CDs and now are stuck with them," lead singer Nick Shuminsky said during the festival. "Most bands that tour have (expletive) vans that still have tape players, and the idea is that at the very least our friends in bands can listen to our record while they're touring."

While Free Energy is a fairly well-known band, their cassette handout is a move that has bubbled up from a much more underground culture that has been thriving since before music stores cleared their shelves of tape to make way for CDs in the early '90s. It continues to be an extremely niche market, but as the once-abandoned medium pops up at more mainstream events, one has to wonder whether tape is poised for a rise similar to vinyl.

Cassette players and tapes do exist — Best Buy, for example, stocks a Sony Walkman and blank cassettes (and VHS tapes, too, in case you break out the VCR). Another place to look is thrift stores — many of them maintain a wall of old tapes, and a variety of cassette players are generally available. Some independently owned Austin record stores, such as End of an Ear, offer cassettes. Tapes also aren't exclusive to young indie rock bands. Pearl Jam and Sonic Youth have released music on cassette recently as well.

On a recent Tuesday night in the KVRX studios in the Jesse H. Jones Communication Center on the University of Texas campus, Brad Barry opened packages as he waited for another DJ to finish her show. He hosts c60, a radio program devoted to cassettes that airs from 11 p.m. to midnight Tuesdays. He posts podcasts of the show that people from across the country, and some from other countries, listen to regularly. Much of the music he plays on the show is experimental — abstract, noisy, and for the most part lacking the verse-chorus song structure common to pop music.

Each envelope he opened held a cassette, or sometimes a set of cassettes; most were from out-of-state, all of them contained some sort of personally designed jacket. That do-it-yourself element is part of what draws people to the world of cassettes, Barry says. "There is a sense of nostalgia," he said. "Punk bands and DIY stuff in the '80s was on cassette, so you kind of want to connect with that lineage — it's a history that's both personal and musical."

Barry, 22, is a senior in UT's Plan II program. His thesis is about experimental music on cassette in the 21st century. The show is an effort to share that music with others. "I was listening to a lot of music, and realized that so many people are never going to hear this, because you don't have a deck or you don't know where to find it," Barry said. "That's why I started the show, because people are going to be able to hear that really cool stuff is coming out on tape even if they don't have the means to listen to it."

Barry isn't the only one in Austin interested in tapes. Seth Whaland, who plays bass in local powerpop band Literature, runs Natrix Natrix Records, one of a handful of small record labels in Austin that releases music on cassette and vinyl only. In addition to his band, he's released music by several bands across the country, including a single by Rhode Island-based indie rock band Deer Tick. Whaland, who moved to Austin in 2005, grew up in Pennsylvania's Lehigh Valley, an area with a tradition of DIY punk and hardcore bands recording music on cassette. He said the hands-on aspect of tape is a big part of the appeal. "I press record on each side — there's actually work that goes into it for me. I love vinyl, but I don't have anything to do with the pressing of it."

Ernest Greene, aka Washed Out, another act that was in town for SXSW and has released music on cassette, said in an interview before the festival that hitting record is part of a larger level of control that cassettes afford artists. "It's pretty great to be able to control every step of the production — like designing the art, printing the labels, dubbing the cassettes. It makes for a much more personal experience," Greene said. "The only way to get one is through me or my website, so it's a pretty simple process, and I think people really enjoy that."

Another benefit is cost: Whaland said a run of 100 tapes costs him about $100. A quick search online reveals a few businesses that will reproduce cassettes for about the same price. (CDs are typically done in batches of 500 minimum for around $750, Phil Waldorf of Austin label Dead Oceans, says. There are some companies that will do smaller numbers; prices average around $2 a CD.) The low price has led to the founding of small tape labels in a lot of places, especially in the Midwest, that don't have a developed music industry.

"Music used to have to come through all of these different middlemen," Barry said. "Now you can be in your hometown, in your bedroom, and make music and ship it to Japan. You don't need anyone else's help to do it."

Even with the increase in the number of tape labels, Barry says that the fact that a relatively small number of people are interested in tapes is part of the fun. Whaland agrees, but wonders if too much popularity will change things. "If a lot of people start doing it," he said, "is it going to become something different?"

Both Barry and Whaland stress that the appeal of cassettes is one of substance over style, however. Music released on cassette is something they truly enjoy.

"It is a venue that a lot of the most interesting and forward-thinking music is coming out on," Barry said. "I don't know if the medium feeds the music or the music feeds the medium, but that's why it's exciting, because it's good music."